Detachment Apparatus Having Arched Drum Pad and Method for Fabricating Lightweight, Thin Liquid Crystal Display Device Using the Same

ABSTRACT

A detachment apparatus having an arched drum pad and a method for fabricating a lightweight, thin liquid crystal display (LCD) device using the same are provided. The detachment apparatus includes: a table to which an object to be processed is loaded; an arched drum pad installed over the table and including O-rings formed on a lower surface thereof and a plurality of vacuum compartments demarcated by the O-rings; and a plurality of driving units configured to control a position of the drum pad. In case of using an auxiliary substrate to perform a process of a thin glass substrate, the auxiliary substrate can be easily separated from a liquid crystal panel in a cell state attached after processes are completed by using the arched drum pad having O-rings and a plurality of vacuum compartments.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. §119(a), to KoreanApplication No. 10-2012-0152377, filed on Dec. 24, 2012, the contents ofwhich is incorporated by reference herein in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present disclosure relates to a method for fabricating a liquidcrystal display device and, more particularly, to a detachment apparatushaving an arched drum pad, and a method for fabricating a lightweightand thin liquid crystal display device using the same.

2. Background of the Invention

Recently, as society has entered a full-fledged information age, displayfields of processing and displaying a large quantity of information hasbeen rapidly advanced, and in particular, a thin film transistor (TFT)liquid crystal display device (LCD) having excellent performance such asbeing lightweight, having a reduced thickness, and consuming a smallamount of power, has been developed to replace existing cathode raytubes (CRTs).

An LCD device includes a color filter substrate, an array substrate anda liquid crystal layer formed between the color filter substrate and thearray substrate.

The color filter substrate includes a color filter including sub-colorfilters that implement red, green and blue colors, a black matrixdemarcating the sub-color filters and blocking light transmissionthrough the liquid crystal layer, and a transparent common electrodeapplying a voltage to the liquid crystal layer.

The array substrate includes gate lines and data lines arrangedvertically and horizontally to define pixel regions. Here, TFTs (T),switching elements, are formed at respective crossings of the gate linesand the data lines, and pixel electrodes are formed on the respectivepixel regions.

The color filter substrate and the array substrate are attached in afacing manner by a sealant (not shown) formed at edges of an imagedisplay region to form a liquid crystal panel, and the attachment of thecolor filter substrate and the array substrate is made by an attachmentkey formed on the color filter substrate or the array substrate.

An LCD device is commonly used in a portable electronic device, so inorder to enhance portability of an electronic device, a size and weightof an LCD device must be reduced. In addition, as a large LCD device hasbeen fabricated, demand for a lighter and thinner LCD device is on therise.

A thickness and weight of an LCD device may be reduced in variousmanners, but there is a limitation in reducing a structure and essentialcomponents of an LCD device in terms of current technologies. Inaddition, weights of essential components are so small that it may bedifficult to reduce an overall thickness or weight of the LCD device byreducing the weights of the essential elements.

Thus, a method for reducing a thickness and weight of an LCD device byreducing a thickness of a color filter substrate and an array substrateconstituting a liquid crystal panel has been actively studied. However,since a thin substrate must be used, when the thin film is transferredbetween a plurality of unit processes or when unit processes areperformed, the thin film may be warped or broken.

SUMMARY OF THE INVENTION

Therefore, an aspect of the detailed description is to provide a methodfor fabricating a lightweight and thin liquid crystal display device inwhich a thin glass substrate is prevented from being damaged byattaching an auxiliary substrate to the thin film glass substrate andperforming processes.

Another aspect of the present invention provides a detachment apparatushaving an arched drum pad capable of easily separate an auxiliarysubstrate from a liquid crystal panel in an attached cell state afterprocesses are completed, and a method for fabricating a lightweight andthin liquid crystal display (LCD) device.

To achieve these and other advantages and in accordance with the purposeof this specification, as embodied and broadly described herein, adetachment apparatus having an arched drum pad includes: a table towhich an object to be processed is loaded; an arched drum pad installedover the table and including O-rings formed on a lower surface thereofand a plurality of vacuum compartments demarcated by the O-rings; and aplurality of driving units configured to control a position of the drumpad.

The object to be processed may be a process-completed liquid crystalpanel in a cell state, and auxiliary substrates may be attached to bothsides of the liquid crystal panel.

The detachment apparatus may further include: a push pin and a gap knifefor forming an initial gap to separate each of the auxiliary substratesfrom the liquid crystal panel.

The detachment apparatus may further include: an air knife jetting airto a gap between the liquid crystal panel and each of the auxiliarysubstrates during a detachment process to allow each of the auxiliarysubstrates to be easily separated.

The plurality of driving units may include an A-axis driving unit, aB-axis driving unit, and a C-axis driving unit adjusting a verticalrotation, a vertical height, and a horizontal position of the drum pad,respectively.

The A-axis driving unit may be connected to one side of the drum pad,and a vertical rotation of the drum pad may be made according to avertical movement of the A-axis driving unit.

The B-axis driving unit may be connected to a central portion of thedrum pad to adjust a vertical height of the entirety of the drum pad,and the C-axis driving unit may be installed between the B-axis drivingunit and the drum pad to adjust a horizontal position of the entirety ofthe drum pad.

Movement values of axes of the respective driving units may be set forrespective points from a point at which detachment of each of theauxiliary substrate starts to a point at which the detachment ends, andaxes of the respective driving units may be moved vertically orhorizontally according to the pre-set values.

The O-rings may include a first O-ring having a rectangular shapeconstituting the rim and a plurality of second O-rings connected to bothsides of the first O-ring and having a lattice shape.

The O-rings may be made of a material having excellent thermal,chemical, and physical durability of natural rubber or silicon.

The vacuum compartments may be demarcated by the first and secondO-rings, have an elongated rectangular shape, include a vacuum grooveline having a trapezoid shape and a plurality of absorption holes formedin the vacuum groove line and extending to an upper surface of the drumpad to form individual vacuum in each of the vacuum compartments.

A surface of the arched drum pad may be coated with fluorine or carbonnano-tube to prevent damage to the auxiliary substrates due to staticelectricity.

To achieve these and other advantages and in accordance with the purposeof this specification, as embodied and broadly described herein, amethod for fabricating a lightweight, thin liquid crystal display (LCD)device includes: providing first and second auxiliary substrates andfirst and second thin mother substrates; attaching the first and secondauxiliary substrates to the first and second thin mother substrates,respectively; performing an array process on the first mother substratewith the first auxiliary substrates attached thereto; performing a colorfilter process on the second mother substrate with the second auxiliarysubstrate attached thereto; attaching the array process-finished firstmother substrate and the color filter process-finished second mothersubstrate; providing a detachment apparatus including an arched drum padhaving O-rings formed on a lower surface thereof and a plurality ofvacuum compartments formed on the lower surface and demarcated by theO-rings; loading the attached first and second mother substrates onto atable of the detachment apparatus; separating the second auxiliarysubstrate from the second mother substrate by using the drum pad;reversing the first and second mother substrates without the secondauxiliary substrate and loading the same onto the table; and separatingthe first auxiliary substrate from the first mother substrate by usingthe drum pad.

The separating of the second auxiliary substrate from the second mothersubstrate may include: lowering a front end of the drum pad andsimultaneously lifting a rear end thereof and absorbing a surface of thefront end of the second auxiliary substrate through the vacuumcompartments of the drum pad; and gradually lifting the front end of thedrum pad with the second auxiliary substrate absorbed thereto, andsimultaneously gradually lowering the rear end of the drum pad toseparate the second auxiliary substrate from the second mothersubstrate.

Before the second auxiliary substrate is separated, push pin regionsexposed from both corners of the second auxiliary substrate may bepushed upward with predetermined pressure by using bar-like push pins toform a gap knife entry space between the second auxiliary substrate andthe second mother substrate.

A gap knife may be introduced into the gap knife entry space and movedfrom one side to the other side of the table to detach edge portionsbetween the second auxiliary substrate and the second mother substrateto form an initial gap.

The separating of the first auxiliary substrate from the first mothersubstrate may include: lowering a front end of the drum pad andsimultaneously lifting a rear end thereof and absorbing a surface of thefront end of the first auxiliary substrate through the vacuumcompartments of the drum pad; and gradually lifting the front end of thedrum pad with the first auxiliary substrate absorbed thereto, andsimultaneously gradually lowering the rear end of the drum pad toseparate the first auxiliary substrate from the first mother substrate.

Before the first auxiliary substrate is separated, push pin regionsexposed from both corners of the first auxiliary substrate may be pushedupward with predetermined pressure by using bar-like push pins to form agap knife entry space between the first auxiliary substrate and thefirst mother substrate.

A gap knife may be introduced into the gap knife entry space and movedfrom one side to the other side of the table to detach edge portionsbetween the first auxiliary substrate and the first mother substrate toform an initial gap.

As described above, according to the method for fabricating alightweight, thin LCD device, a lightweight, thin LCD device using athin glass substrate can be implemented, and thus, a thickness andweight of a television or monitor model and a portable electronicdevice.

Also, in the case of the detachment apparatus having an arched drum padand the method for fabricating a lightweight, thin LCD device using thesame, the auxiliary substrates can be easily separated from the liquidcrystal panel in a cell state attached after processes are completed, byusing the arched drum pad having O-rings and a plurality of vacuumcompartments. Thus, a tact time can be minimized and the processes arestabilized, enhancing price competitiveness of a product.

Further scope of applicability of the present application will becomemore apparent from the detailed description given hereinafter. However,it should be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from the detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate exemplary embodiments andtogether with the description serve to explain the principles of theinvention.

FIG. 1 is a flow chart schematically illustrating a method forfabricating a lightweight, thin liquid crystal display (LCD) deviceaccording to an embodiment of the present invention.

FIGS. 2A through 2D are views schematically illustrating portions ofprocesses of method for fabricating a lightweight, thin liquid crystaldisplay (LCD) device according to an embodiment of the presentinvention.

FIGS. 3A and 3B are plan views schematically illustrating first andsecond auxiliary substrates and first and second mother substrates withcut corners according to an embodiment of the present invention.

FIG. 4 is a plan view illustrating first and second mother substrates inwhich push pin regions are formed as the first and second auxiliarysubstrates with the cut corners are attached thereto according to anembodiment of the present invention.

FIG. 5 is a view schematically illustrating a configuration of adetachment apparatus having an arched drum pad according to anembodiment of the present invention.

FIG. 6 is a graph showing shaft movement values over a control point ofa driving unit in the detachment apparatus according to an embodiment ofthe present invention.

FIG. 7 is a perspective view schematically illustrating a configurationof an arched drum pad in the detachment apparatus according to anembodiment of the present invention.

FIG. 8 is a view schematically illustrating a cross-section of thearched drum pad of FIG. 7 taken along line A-A.

FIGS. 9A and 9B are views illustrating absorption surface of the archeddrum pad illustrated in FIG. 7.

FIG. 10 is a flow chart illustrating a process of separating anauxiliary substrate in the method for fabricating a lightweight, thinLCD device according to an embodiment of the present invention.

FIGS. 11A through 11L are cross-sectional views sequentiallyillustrating the process of separating an auxiliary substrate in themethod for fabricating a lightweight, thin LCD device according to anembodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Description will now be given in detail of the exemplary embodiments,with reference to the accompanying drawings. For the sake of briefdescription with reference to the drawings, the same or equivalentcomponents will be provided with the same reference numbers, anddescription thereof will not be repeated.

Recently, as purposes of liquid crystal display (LCD) devices have beendiversified, interest in lightweight, thin LCD devices are on the riseand thinning of a substrate taking the largest share in a thickness of aliquid crystal panel is growing. Also, a 3D or touch panel additionallyrequires a retarder or a touch function protection substrates to beattached to a liquid crystal panel, demand for reducing a thicknessthereof is increasing. However, in the case of a thin substrate,physical properties such as warpage (or bowing), rigidness, and thelike, are weakened, having a limitation in performing a process.

As a solution, a method for attaching an auxiliary substrate to a thinglass substrate, performing a process, and separating the auxiliarysubstrate from the thin glass substrate after the process is completedhas been attempted. In particular, in an embodiment of the presentinvention, an auxiliary substrate is attached to a glass substrate byusing electrostatic force, vacuum force, surface tension, or the like,and processes are performed thereon, and the auxiliary substrateattached to the liquid crystal panel in a cell state through the processis easily separated from the liquid crystal panel by using an archeddrum pad having O-rings and a plurality of vacuum compartments.

Hereinafter, a detachment apparatus having an arched drum pad and amethod for fabricating a lightweight, thin liquid crystal display (LCD)device using the same according to an embodiment of the presentinvention will be described in detail such that a person skilled in theart can easily carry out the same.

The foregoing and other objects, features, aspects and advantages of thepresent invention will be described in detail through embodimentsdescribed hereinafter in conjunction with the accompanying drawings.However, embodiments of the present invention may, however, beimplemented in many different forms and should not be construed as beinglimited to the embodiments set forth herein. Rather, these embodimentsare provided so that this disclosure will be thorough and complete, andwill fully convey the scope of the invention to those skilled in the artand are defined by the claim coverage of the present invention.Throughout the specification, the same reference numerals will be usedto designate the same or like components.

FIG. 1 is a flow chart schematically illustrating a method forfabricating a lightweight, thin liquid crystal display (LCD) deviceaccording to an embodiment of the present invention.

Here, FIG. 1 illustrates an example of a method for fabricating a liquidcrystal display device when a liquid crystal layer is formed accordingto a liquid crystal dispensing method, but the present invention is notlimited thereto and may also be applied to a method for fabricating anLCD device when a liquid crystal layer is formed according to a liquidcrystal injection method.

A process of fabricating an LCD device may be divided into a drivingelement array process of forming a driving element on a lower arraysubstrate, a color filter process of forming color filters on an uppercolor filter substrate, and a cell process.

As mentioned above, factors affecting a thickness and weight of an LCDdevice may be diverse, and among them, the array substrate or the colorfilter substrate made of glass are the heaviest among other components.Thus, in order to reduce a thickness and weight of the LCD device, it ismost effective to reduce a thickness or weight of the glass substrates.

In order to reduce a thickness and weight of the glass substrates, theglass substrates are etched to reduce a thickness thereof or a thinglass substrate is used. The first method is reducing the thickness byadditionally performing a glass etching process after a cell iscompleted. This method, however, is disadvantageous in that a defectoccurs during the etching process and cost is increased.

Thus, in an embodiment of the present invention, an array process, acolor filter process, and a cell process are performed by using a thinglass substrate having a thickness ranging from 0.1 t to 0.4 t. In thiscase, since the thin glass substrate is attached to an auxiliarysubstrate and the processes are performed, influence of warpage of thethin glass substrate is minimized and the thin glass substrate is notdamaged when it is transferred. Here, ‘t’ refers to mm. Namely, 0.1 trefers to a thickness of 0.1 mm and 0.4 t refers to a thickness of 0.4mm. In the following description, mm will be denoted by ‘t’ for thedescription purpose.

Namely, the thin glass substrate having a thickness ranging from 0.1 tto 0.4 t is significantly warped when put into a general LCD devicefabrication line, resulting in that the substrate is severely sagged,having a problem that it is difficult for the substrate to betransferred by using a moving means such as a cassette, or the like.Also, when the substrate is loaded into or unloaded from unit processequipment, the substrate is rapidly warped even with small impactapplied thereto, frequently causing a position error, and as a result,the substrate is damaged due to collision, or the like, substantiallymaking it impossible to perform the process.

Thus, in the present embodiment, an auxiliary substrate is attached tothe thin glass substrate having a thickness ranging from 0.1 t to 0.4 tbefore the substrate is put into a fabrication line, to allow thesubstrate to have the same warpage characteristics as or more enhancedwarpage characteristics than those of a glass substrate having athickness of approximately 0.7 used in a general LCD device, thuspreventing sagging of the substrate while being transferred to while aunit process is being performed.

First, before a thin glass substrate having a thickness ranging from 0.1t to 0.4 t is put into a fabrication line of an array process or a colorfilter process, an auxiliary substrate having a thickness ranging from0.3 t to 0.7 t is attached to the thin glass substrate having athickness ranging from 0.1 t to 0.4 t (S101). However, the presentinvention is not limited to the thickness of the thin glass substrateand the auxiliary substrate.

The thin glass substrate and the auxiliary substrate may be brought intocontact in a vacuum state so as to be attached. In this case, bondingstrength between the two substrates may be based on vacuum force, vander Waals force, electrostatic force, molecular binding, and the like.

Here, the auxiliary substrate may be subjected to plasma processingusing fluorine, or the like, or surfactant processing, or aconcave-convex pattern may be formed on the auxiliary substrate toalleviate bonding strength to facilitate detachment of the auxiliarysubstrate from the thin glass substrate. This will be described indetail with reference to the accompanying drawings. However, the presentinvention is not limited thereto and the thin glass substrate and theauxiliary

FIGS. 2A through 2D are views schematically illustrating portions ofprocesses of method for fabricating a lightweight, thin liquid crystaldisplay (LCD) device according to an embodiment of the presentinvention, in which an example of processes of attaching and detachingthe thin glass substrate and the plasma or surfactant-processedauxiliary substrate is shown.

Here, in FIGS. 2A through 2D, a plasma or surfactant treatment isperformed on the entire surface of the auxiliary substrate to alleviatebonding strength between the auxiliary substrate and the thin glasssubstrate to facilitate attachment and detachment between the auxiliarysubstrate and the thin glass substrate. However, the present inventionis not limited thereto.

As illustrated in FIG. 2A, for example, thin glass substrate 100 havinga thickness ranging from 0.1 t to 0.4 t and an auxiliary substrate 110having a thickness ranging from 0.3 t to 0.7 t are prepared.

Here, the thin glass substrate 100 may be a large mother substrate inwhich a plurality of color filter substrates for a color filter processare disposed or a large mother substrate in which a plurality of arraysubstrates for an array substrate are disposed.

Next, as illustrated in FIG. 2B, the entire surface 111 of the auxiliarysubstrate 110 is treated with a surfactant or plasma using fluorine, orthe like.

When the auxiliary substrate 110 is treated with fluorine, fluorineetches the surface 111 of the auxiliary substrate 110 to increasesurface roughness or change chemical characteristics of the surface ofthe auxiliary substrate 110 to weaken bonding strength with the thinglass substrate 100 through contact.

Alternatively, in a case in which the auxiliary substrate 110 is treatedwith a surfactant when cleaned, —OH group between the auxiliarysubstrate 110 and the thin glass substrate 100 may be reduced, thusmitigating bonding strength therebetween.

Thereafter, as illustrated in FIG. 2C, the auxiliary substrate 110treated with plasma or a surfactant is attached to the thin glasssubstrate 100. Here, in a case in which a glass substrate is used as theauxiliary substrate 100, the thin glass substrate 100 and the auxiliarysubstrate 110 may be brought into contact in a vacuum state so as to beattached, and in this case, the bonding strength between the twosubstrates 100 and 110 may be based on vacuum force, van der Waalsforce, electrostatic force, molecular binding, and the like.

In this manner, in the case of the process panel obtained by attachingthe thin glass substrate 100 having the thickness ranging from 0.1 t to0.4 t and the auxiliary substrate 110 having the thickness ranging from0.3 t to 0.7 t, since the thin glass substrate 100 and the auxiliarysubstrate 110 constituting the process panel are made of the same glassmaterial, coefficients of expansion according to a change in temperatureare the same, eliminating the process in which warpage occurs due to adifference in coefficients of expansion in performing unit processes.

Also, although the thin glass substrate 100 has the thickness rangingfrom 0.1 t to 0.4 t, since it is attached with the auxiliary substrate110 to form a process panel, warpage thereof is remarkably reduced.Also, since the glass substrate 100 with the auxiliary substrate 110attached thereto has a warpage level, which is the same as or less thanthat of a general glass substrate having a thickness of 0.7 t, there isno problem in performing a unit process for an LCD device.

Thereafter, a color filter process or an array process as describedhereinafter is performed on the thin glass substrate 100 with theauxiliary substrate 110 attached thereto to form thin film transistors(TFTs) as driving elements or a color filter layer in respective panelregions.

After a predetermined process is completed, as illustrated in FIG. 2D,the auxiliary substrate 110 is required to be separated from the thinglass substrate 100. Here, since the entire surface 111 of the auxiliarysubstrate 110 have been treated with plasma or surfactant, the auxiliarysubstrate 110 can be easily detached.

Namely, if bonding strength between the thin glass substrate 100 and theauxiliary substrate 110 is strong, it is difficult to physicallyseparate the auxiliary substrate 110, so when the auxiliary substrate110 is separated, the thin glass substrate 100 may be warped. However,in the case that the entire surface 111 of the auxiliary substrate 110is plasma-treated, bonding strength between the thin glass substrate 100and the auxiliary substrate 110 is lowered, facilitating separation ofthe auxiliary substrate 110. Alternatively, when the auxiliary substrate110 is treated with a surfactant, OH groups between the auxiliarysubstrate 110 and the thin glass substrate 100 are reduced to mitigatebonding strength therebetween.

The auxiliary substrate 110 separated from the thin glass substrate 100may be attached to a new glass substrate so as to be recycled forperforming a new process.

Meanwhile, the method of treating the auxiliary substrate with plasmaincludes a partial surface processing method, in addition to theforegoing entire surface processing method. For example, in order tofacilitate separation of the auxiliary substrate, a plasma treatmentusing fluorine, or the like, may be performed on a central partialsurface of the auxiliary substrate. In this case, since only a partialsurface of the auxiliary substrate is treated with fluorine, attachmentis made in a region in which the both substrates can be in contact, andwhen the auxiliary substrate is separated, the auxiliary substrate canbe easily separated due to the fluorine-treated region, namely, thepartial surface.

Also, in the foregoing cases, the auxiliary substrate is treated withplasma or a surfactant to mitigate bonding strength between theauxiliary substrate and the thin glass substrate to facilitateseparation of the auxiliary substrate, but the present invention is notlimited thereto. In an embodiment of the present invention, a depressionand protrusion pattern may be formed on the auxiliary substrate tomitigate bonding strength between the auxiliary substrate and the thinglass substrate. The method of forming a depression and protrusionpattern may include inorganic insulating layer patterning, organicinsulating layer patterning, low temperature SiO2 etching, laserpatterning method, and the like. When a depression and protrusionpattern is formed on the auxiliary substrate, surface roughness isincreased to weaken bonding strength between the auxiliary substrate andthe thin glass substrate.

However, the present invention is not limited to the foregoing auxiliarysubstrate attaching method. As mentioned above, in an embodiment of thepresent invention, the auxiliary substrate may be attached to the thinglass substrate in a vacuum state without using an adhesive or surfaceprocessing, and in this case, the two substrates may be attached throughelectrostatic force, vacuum force, van der Waals force, surface tension,and the like.

Meanwhile, a detachment method applicable to the foregoing cases mayinclude a method of catching an upper portion of the auxiliary substrateor the thin glass substrate with a vacuum pad to lift the auxiliarysubstrate or the thin glass substrate. In this case, since the surfaceof the auxiliary substrate is treated with plasma or a surfactant or hasa depression and protrusion pattern formed thereon, bonding strengthbetween the two substrates is not so strong and the auxiliary substratecan be easily separated. However, the vacuum pad has a flat absorptionsurface to generate tension due to vertical detachment. Thus, in a spotat which detachment starts or ends, the auxiliary substrate may bedamaged, which, thus, is required to be improved.

Thus, in an embodiment of the present invention, in order to facilitatedetachment without damaging the auxiliary substrate, an arched drum padhaving O-rings and a plurality of vacuum compartments is used. This willbe described later.

After the auxiliary substrate is attached to the thin glass substrate,the thin glass substrate for an array substrate (hereinafter, it will bereferred to as an ‘array substrate’ for the description purpose) withthe forgoing auxiliary substrate attached thereto is undergone an arrayprocess. Namely, through the array process, a plurality of gate linesand a plurality of data lines are arranged to define pixel regions onthe array substrate, and thin film transistors (TFT) as driving elementsconnected to the gate lines and the data lines are formed in therespective pixel regions (S102). Also, through the array process, pixelelectrodes are formed to be connected to the TFTs and drive liquidcrystal layers as a signal is applied thereto through the TFTs.

Also, color filter layers including red, green, and blue sub-colorfilters implementing colors and common electrodes are formed on the thinglass substrate with the foregoing auxiliary substrate attached thereto(hereinafter, referred to as a ‘color filter substrate’ for thedescription purpose) through a color filter process (S103). Here, incase of fabricating an in-plane switching (IPS) LCD device, the commonelectrode is formed on the array substrate with pixel electrodes formedthereon through the array process.

Subsequently, alignment films are printed on the color filter substrateand the array substrate, respectively, and rubbed to provide anchoringforce or surface fixing force (i.e., a pretilt angle and an alignmentdirection) to liquid crystal molecules of the liquid crystal layerformed between the color filter substrate and the array substrate (S104,S105).

A sealing material is applied to the rubbed color filter substrate toform a predetermined seal pattern, and liquid crystal is dropped to thearray substrate to form a liquid crystal layer (S106, S107).

Meanwhile, the color filter substrate and the array substrate are formedon a large mother substrate, respectively. In other words, a pluralityof panel regions are formed on each of the large mother substrates, andTFTs as driving elements or color filter layers are formed in each ofthe plurality of panel regions.

In this case, the dropping method is a method in which liquid crystal isdropped and dispensed to an image display region of a first large mothersubstrate on which a plurality of array substrates are disposed or asecond large mother substrate in which a plurality of color filtersubstrates are disposed by using a dispenser. The liquid crystal isuniformly distributed to the entirety of the image display region bypressure for attaching the first and second mother substrates, thusforming a liquid crystal layer.

Thus, in the case of forming the liquid crystal layer on the liquidcrystal panel through a dropping method, a seal pattern is required tobe formed as a closed pattern surrounding the outer edge of a pixel partregion to prevent liquid crystal from being leaked to the outside of theimage display region.

Through the dropping method, liquid crystal may be dropped within ashort time, relative to a vacuum injection method, and even when theliquid crystal panel has a large size, the liquid crystal layer can bevery rapidly formed. Also, since only a required amount of liquidcrystal is dropped to the substrate, an increase in cost of the liquidcrystal panel because high-priced liquid crystal is discarded, as in thevacuum injection method, is prevented, strengthening pricecompetitiveness of a product.

Thereafter, in a state in which the first mother substrate and thesecond mother substrate with the liquid crystal dropped thereto and asealing material coated thereon are aligned, pressure is applied theretoto attach the first and second mother substrates by the sealing materialand allow the dropped liquid crystal to be uniformly spread on theentire liquid crystal panel (S108). Through this process, a plurality ofliquid crystal panels including a liquid crystal layer formed thereon reformed on the first and second large mother substrates. After the firstand second auxiliary substrates are separated from the first and secondlarge mother substrates with the plurality of liquid crystal panelsformed thereon, the first and second mother substrates are cut into aplurality of liquid crystal panels, and each liquid crystal panel isinspected (S109, S110).

Here, as mentioned above, in an embodiment of the present invention, theauxiliary substrate is separated from the liquid crystal panel by usingan arched drum pad, and in this case, the formation of a push pin regionby using a corner cut facilitates the separation of the auxiliarysubstrate. This will be described in detail with reference to theaccompanying drawings.

FIGS. 3A and 3B are plan vies schematically illustrating first andsecond auxiliary substrates and first and second mother substrates withcut corners.

FIG. 4 is a plan view illustrating first and second mother substrates inwhich push pin regions are formed as the first and second auxiliarysubstrates with the cut corners are attached thereto.

Referring to the drawings, as described above, in an embodiment of thepresent invention, before thin glass substrates, i.e., the first andsecond mother substrates 101 and 102, having a thickness ranging from0.1 t to 0.4 t is put into a fabricating line, the first and secondauxiliary substrate 110 a and 110 b having a thickness ranging from 0.3t to 0.7 t are attached thereto to have warpage generationcharacteristics the same as or better than those of a glass substratehaving a thickness of approximately 0.7 t used in a general LCD device,whereby sagging of the substrate, or the like, is prevented while it iscarried or a unit process is performed thereon.

Here, the corners of the first and second mother substrates 101 and 102and the first and second auxiliary substrates 110 a and 110 b in anattached state with the plurality of liquid crystal panels 103 assignedthereto are cut at a predetermined tilt angle, which is called a cornercut.

In particular, at least two corners of the first and second mothersubstrates 101 and 102 are cut further in an inward direction in orderto distinguish directions and post-processing, so corner portions of thefirst and second auxiliary substrates 110 a and 110 b are exposed. Theexposed regions may be used as push pin regions A and B to start aprocess of separating the first and second auxiliary substrates 110 aand 110 b.

Hereinafter, a method for separating an auxiliary substrate from aliquid crystal panel in an attached cell state after processes arecompleted will be described in detail with reference to the accompanyingdrawings.

FIG. 5 is a view schematically illustrating a configuration of adetachment apparatus having an arched drum pad according to anembodiment of the present invention.

FIG. 6 is a graph showing shaft movement values over a control point ofa driving unit in the detachment apparatus according to an embodiment ofthe present invention.

FIG. 7 is a perspective view schematically illustrating a configurationof an arched drum pad in the detachment apparatus according to anembodiment of the present invention.

FIG. 8 is a view schematically illustrating a cross-section of thearched drum pad of FIG. 7 taken along line A-A.

FIGS. 9A and 9B are views illustrating absorption surface of the archeddrum pad illustrated in FIG. 7. Here, FIG. 9B is an enlarged view of aportion B of an absorption surface of the arched drum pad illustrated inFIG. 9A.

Referring to FIG. 5, a detachment apparatus 170 according to anembodiment of the present invention includes a table 173 provided in aframe 172 and allowing an object to be processed to be installedthereon, a drum pad 180 installed above the table 173, and a pluralityof driving units 171 a, 171 b, and 171 c controlling a position of thedrum pad 180.

In this case, for example, the object to be processed may be a liquidcrystal panel in a cell state after a process is completed, and here,auxiliary substrates are attached to both sides of the liquid crystalpanel for performing a process on a thin glass substrate.

In order to separate the auxiliary substrates from the process-completedliquid crystal panel, the detachment apparatus 170 may further includeauxiliary detachment equipment 174 including a push pin and a gap knife.The auxiliary detachment equipment 174 may be installed in one side orin both sides of the table 173.

Also, the detachment apparatus 170 according to an embodiment of thepresent invention may further include an air knife 175 jetting air to agap between the liquid crystal panel and the auxiliary substrate in adetachment process such that the auxiliary substrate can be easilyseparated.

The plurality of driving units 171 a, 171 b, and 171 c may include anA-axis driving unit 171 a, a B-axis driving unit 171 b, and a C-axisdriving unit 171 c adjusting a vertical rotation, a vertical height, anda horizontal position of the drum pad 180, respectively. For example,the plurality of driving units 171 a, 171 b, and 171 c may be configuredas servo motors.

The A-axis driving unit 171 a may be connected to one side of the drumpad 180, and a vertical rotation of the drum pad 180 may be madeaccording to a vertical movement of the A-axis driving unit 171 a.

The B-axis driving unit 171 b may be connected to a central portion ofthe drum pad 180 to adjust a vertical height of the entirety of the drumpad 180. The C-axis driving unit 171 c may be installed between theB-axis driving unit 171 b and the drum pad 180 to adjust a horizontalposition of the entirety of the drum pad 180.

While detachment is being performed, axes of the A-axis driving unit 171a and the B-axis driving unit 171 b are moved in a vertical direction,and an axis of the C-axis driving unit 171 c is moved in a horizontaldirection.

For example, referring to FIG. 6, in order to detach the auxiliarysubstrate by using the drum pad 180, movement values of the axes of therespective driving units 171 a, 171 b, and 171 c may be set inrespective points from a point (point 0) at which detachment starts to apoint (point 92) at which detachment is terminated, and axes of therespective driving units 171 a, 171 b, and 171 c are moved vertically orhorizontally.

In this case, the case in which the movement values of the axes of therespective driving units 171 a, 171 b, and 171 c are set according to atotal of 93 control points is taken as an example, but it is merelyillustrative and the present invention is not limited thereto.

In this manner, since the plurality of driving units 171 a, 171 b, and171 c including three axes are used and coordinate axes of therespective driving units 171 a, 171 b, and 171 c are calculated and set,the auxiliary substrate can be detached while the table 173 and the drumpad 180 are positioned at a predetermined interval therebetween.

The auxiliary substrate detached from the liquid crystal panel andattached to the drum pad 180 may undergo a separation process performedin reverse order of the detachment process, whereby the auxiliarysubstrate can be separated from the drum pad 180.

Here, the table 173 according to an embodiment of the present inventionmay have a temperature ranging from 100° C. to 150° C. For example, whenglass and glass are separated, if the table 173 is maintained at atemperature of approximately 100° C., bonding strength may be reduced tohalf (½). Thus, since bonding strength is reduced, when the auxiliarysubstrate is detached from the liquid crystal panel, less stress isapplied to the auxiliary substrate, preventing glass damage, a cellrigidity degradation.

According to results of checking a change in detachment force accordingto a temperature of the table 173, it can be seen that, when theauxiliary substrate is detached at a temperature of 110° C., thedetachment force is reduced by about 0.5 kgf, in comparison to the casethe auxiliary substrate is detached at room temperature (about 1.16kgf).

Referring to FIGS. 7, 8, 9A, and 9B, the drum pad 180 according to anembodiment of the present invention has an arc shape with apredetermined curvature, and include O-rings 184 formed on a lowersurface, i.e., an absorption surface, thereof and a plurality of vacuumcompartments 185 formed on the lower surface and demarcated by theO-rings 184.

The O-rings 184 may include a first O-ring 184 a having a rectangularshape constituting the rim and a plurality of second O-rings 184 bconnected to both sides of the first O-ring 184 and having a latticeshape.

Here, in order to minimize damage to the auxiliary substrate whendetached, the O-rings 184 may be made of a material having a low degreeof hardness (within 30), and a surface of the O-ring 184 may be coatedto allow the auxiliary substrate to be easily detached from the archeddrum pad 180.

Namely, in order to provide excellent absorptive power and preventdamage to the auxiliary substrate, the O-ring 184 may be made of a softmaterial having excellent thermal, chemical, and physical durabilitysuch as natural rubber, silicon, or the like. If the O-ring 184 is madeof a material having adhesion, a material reducing adhesion may becoated on the surface of the O-ring 184 to use the O-ring 184 in orderto eliminate a possibility of damage to the auxiliary substrate.

The vacuum compartments 185 are demarcated by the first and secondO-rings 184 a and 184 b and have an elongated rectangular shape. Eachvacuum compartment 185 includes a vacuum groove line 183 having atrapezoid shape and a plurality of absorption holes 181 formed in thevacuum groove line 183 and extending to an upper surface of the drum pad180, forming individual vacuum in each of the vacuum compartments 185.

As mentioned above, when the auxiliary substrate is detached by usingthe absorption pad with a flat lower surface, force applied to theentire surface thereof may strongly act on a point at which detachmentstarts or ends temporarily, and in this case, the auxiliary substratemay be damaged or the equipment may be overloaded.

Thus, in an embodiment of the present invention, the lower surface ofthe drum pad 180 is formed to have an arched shape, recesses 182 areformed on the lower curved surface of the drum pad 180 and the first andsecond O-rings 184 a and 184 b are inserted therein to form theplurality of vacuum compartments 185 to allow the vacuum compartments185 individually absorb the auxiliary substrate.

Also, as mentioned above, the absorption hole 181 is formed to penetratethrough the drum pad 180, and vacuum may be formed through theabsorption hole 181.

As for the formation of vacuum by each vacuum compartment 185, vacuumingis performed by the vacuum compartments sequentially or wholly by usinga vacuum ejector or a vacuum pump, and as the drum pad 180 passes abovethe auxiliary substrate, it sequentially absorbs the auxiliarysubstrate.

A surface of the arched drum pad 180 may be coated with fluorine orcarbon nano-tube in order to prevent damage to the auxiliary substratedue to static electricity.

In the drum pad 180 according to an embodiment of the present invention,the vacuum compartments 185 may be designed such that a non-absorptionregion is minimized and a size of each vacuum compartment is minimized.

Also, a protrusion height of the O-ring 184 is minimized to preventdamage to the auxiliary substrate due to a step of the O-ring 184.

Hereinafter, a method for separating the auxiliary substrate from theliquid crystal panel in an attached cell state after the processes arecompleted will be described in detail with reference to the accompanyingdrawings.

FIG. 10 is a flow chart illustrating a process of separating anauxiliary substrate in the method for fabricating a lightweight, thinLCD device according to an embodiment of the present invention.

FIGS. 11A through 11L are cross-sectional views sequentiallyillustrating the process of separating an auxiliary substrate in themethod for fabricating a lightweight, thin LCD device according to anembodiment of the present invention. However, the present invention isnot limited to the order of the separation processes of the auxiliarysubstrate illustrated in FIGS. 11A through 11I.

As illustrated in FIG. 11A, in order to separate the first and secondauxiliary substrates 110 a and 110 b, which were attached to the firstand second mother substrates 101 and 102 after the processes werecompleted, from the first and second mother substrates 101 and 102,first, the first and second mother substrates 101 and 102 are loadedonto the table 173 of the detachment apparatus according to anembodiment of the present invention (S201).

Here, the first mother substrate 101 with the TFT array substratesformed thereon and the second mother substrate 102 with the color filtersubstrates formed thereon are formed of thin glass substrate having athickness ranging from 0.1 t to 0.4 t, and in this case, in order toperform processes, the first and second mother substrates 101 and 102may be treated with plasma or a surfactant or first and second auxiliarysubstrates 110 a and 110 b having a depression and protrusion patternformed thereon and having a thickness ranging from 0.3 t to 0.7 t may beattached thereto. However, the first and second thin mother substrates101 and 102 and the first and second auxiliary substrates 110 a and 110b are not limited to the foregoing thicknesses.

The first and second thin mother substrates 101 and 102 and the firstand second auxiliary substrates 110 a and 110 b may be brought intocontact to be attached in a vacuum state, in this case, bonding strengthbetween the two substrates 101 and 110 a and 102 and 110 b may be basedon vacuum force, van der Waals force, electrostatic force, molecularbinding, and the like.

In this case, for example, the first and second mother substrates 101and 102 are loaded onto the table 173 such that the second auxiliarysubstrate 110 b to be separated faces upward, and the arched drum pad180 according to an embodiment of the present invention is installedabove the loaded first and second mother substrates 101 and 102.

The first and second mother substrates 101 and 102 loaded on the table173 are aligned with the drum pad 180 thereabove through a predeterminedaligning unit (S202).

Thereafter, as illustrated in FIG. 11B, push pin regions exposed fromboth corners of the second auxiliary substrate 110 b are pushed upwardlywith predetermined pressure by using a bar-type push pin 174 a to form agap knife entry space between the second auxiliary substrate 110 b andthe thin glass substrate, i.e., the second mother substrate 102(S203-1).

As illustrated in FIG. 11C, a predetermined gap knife 175 is insertedinto a corner space between the second auxiliary substrate 110 b and thesecond mother substrate 102, i.e., the gap knife entry space, andtransferred from one direction of the table 173 to the other directionthereof to detach edge portions between the second auxiliary substrate110 b and the second mother substrate 102 to form an initial gap(S203-2). However, the present invention is not limited to the foregoinginitial gap formation method.

Thereafter, as illustrated in FIG. 11D, by lowering a front end of thedrum pad 180 and simultaneously lifting a rear end thereof, a frontsurface of the second auxiliary substrate 110 b is absorbed through thevacuum compartments in the front end of the drum pad 180. However, thepresent invention is not limited thereto.

As illustrated in FIGS. 11E, 11F, and 11G, in a state in which thesecond auxiliary substrate is absorbed, the front end of the drum pad180 is gradually lifted and the rear end thereof is gradually loweredsimultaneously, thus completing detachment of the second auxiliarysubstrate 110 b (S203-3, S203). At this time, the second auxiliarysubstrate 110 b is absorbed from the front end toward the rear endthereof by the vacuum compartments of the drum pad 180, whereby thesecond auxiliary substrate 110 b is separated.

Here, as described above, the axes of the respective driving units arevertically or horizontally moved according to values previously set foreach point of the second auxiliary substrate 110 b from a point at whichdetachment starts to a point at which detachment ends.

Thus, since the coordinate axes of the respective driving units aremoved according to the pre-set values by using the plurality of drivingunits including three axes, the auxiliary substrate can be detachedwhile the table 173 and the drum pad 180 are positioned at apredetermined interval therebetween.

In this manner, a separating process of the second auxiliary substrate110 b, which was attached to the drum pad 180 after having been detachedfrom the first and second mother substrates 101 and 102, is performed inreverse order of the detaching process, so the second auxiliarysubstrate 110 b can be separated from the drum pad 180 and recycled.

Thereafter, as illustrated in FIG. 11H, the first and second mothersubstrates 101 and 102 without the second auxiliary substrate arereversed and loaded onto the table 173 of the detachment apparatus(S204).

Namely, the first and second mother substrates 101 and 102 are loadedsuch that the first auxiliary substrate 110 a to be separated facesupward, and the foregoing arched drum pad 180 is installed above thefirst and second mother substrates 101 and 102.

The first and second mother substrates 101 and 102 loaded on the table173 of the detachment apparatus are aligned with the drum pad 180thereabove through an aligning unit as mentioned above (S205).

Thereafter, as illustrated in FIG. 11I, the push pin regions exposedfrom both corners of the first auxiliary substrate 110 a are pressedupward with predetermined pressure by using the push pin 174 a to form agap knife entry space between the first auxiliary substrate 110 a andthe thin glass substrate, i.e., the first mother substrate 101 (S206-1).

As illustrated in FIG. 11J, the predetermined gap knife 175 is insertedinto a corner space between the second auxiliary substrate 110 a and thefirst mother substrate 101, i.e., the gap knife entry space, andtransferred from one direction of the table 173 to the other directionthereof to detach edge portions between the first auxiliary substrate110 a and the first mother substrate 101 to form an initial gap(S206-2). However, the present invention is not limited to the foregoinginitial gap formation method.]

Thereafter, as illustrated in FIG. 11K, by lowering the front end of thedrum pad 180 and simultaneously lifting the rear end thereof, a frontsurface of the first auxiliary substrate 110 a is absorbed through thevacuum compartments in the front end of the drum pad 180. However, thepresent invention is not limited thereto.

As illustrated in FIG. 11L, in a state in which the second auxiliarysubstrate is absorbed, the front end of the drum pad 180 is graduallylifted and the rear end thereof is gradually lowered simultaneously,thus completing detachment of the first auxiliary substrate 110 a(S206-3, S206). In this case, the first auxiliary substrate 110 a isabsorbed from the front end toward the rear end thereof by the vacuumcompartments of the drum pad 180, whereby the first auxiliary substrate110 a is separated.

Here, as described above, the axes of the respective driving units arevertically or horizontally moved according to values previously set foreach point of the first auxiliary substrate 110 a from a point at whichdetachment starts to a point at which detachment ends.

Thus, since the coordinate axes of the respective driving units aremoved according to the pre-set values by using the plurality of drivingunits including three axes, a predetermined space is maintained betweenthe table 173 and the drum pad 180 and the first auxiliary substrate 110a may be detached.

In this manner, a separating process of the first auxiliary substrate110 a, which was attached to the drum pad 180 after having been detachedfrom the first and second mother substrates 101 and 102, is performed inreverse order of the detaching process, so the first auxiliary substrate110 a can be separated from the drum pad 180 and recycled.

As described above, the method for fabricating a lightweight, thin LCDdevice according to an embodiment of the present invention, theauxiliary substrate can be easily separated from the liquid crystalpanel in an attached cell state after processes are completed, by usingthe arched drum pad having O-rings and a plurality of vacuumcompartments. As a result, a tack time can be minimized and theprocesses are stabilized, enhancing price competitiveness of theproduct.

The foregoing embodiments and advantages are merely exemplary and arenot to be considered as limiting the present disclosure. The presentteachings can be readily applied to other types of apparatuses. Thisdescription is intended to be illustrative, and not to limit the scopeof the claims. Many alternatives, modifications, and variations will beapparent to those skilled in the art. The features, structures, methods,and other characteristics of the exemplary embodiments described hereinmay be combined in various ways to obtain additional and/or alternativeexemplary embodiments.

As the present features may be embodied in several forms withoutdeparting from the characteristics thereof, it should also be understoodthat the above-described embodiments are not limited by any of thedetails of the foregoing description, unless otherwise specified, butrather should be considered broadly within its scope as defined in theappended claims, and therefore all changes and modifications that fallwithin the metes and bounds of the claims, or equivalents of such metesand bounds are therefore intended to be embraced by the appended claims.

What is claimed is:
 1. A detachment apparatus for separating anauxiliary substrate from an object to be processed, the detachmentapparatus comprising: a table configured to load the object to beprocessed; an arched drum pad installed over the table and includingO-rings formed on a lower surface thereof and a plurality of vacuumcompartments demarcated by the O-rings; and a plurality of driving unitsconfigured to control a position of the drum pad.
 2. The detachmentapparatus of claim 1, wherein the object to be processed is aprocess-completed liquid crystal panel in a cell state, and auxiliarysubstrates are attached to both sides of the liquid crystal panel. 3.The detachment apparatus of claim 2, further comprising: a push pin anda gap knife for forming an initial gap to separate each of the auxiliarysubstrates from the liquid crystal panel.
 4. The detachment apparatus ofclaim 2, further comprising: an air knife jetting air to a gap betweenthe liquid crystal panel and each of the auxiliary substrates during adetachment process to facilitate separation of each of the auxiliarysubstrates.
 5. The detachment apparatus of claim 1, wherein theplurality of driving units include an A-axis driving unit, a B-axisdriving unit, and a C-axis driving unit adjusting a vertical rotation, avertical height, and a horizontal position of the arched drum pad,respectively.
 6. The detachment apparatus of claim 5, wherein the A-axisdriving unit is connected to one side of the arched drum pad, and avertical rotation of the arched drum pad is made according to a verticalmovement of the A-axis driving unit.
 7. The detachment apparatus ofclaim 5, wherein the B-axis driving unit is connected to a centralportion of the arched drum pad to adjust a vertical height of theentirety of the arched drum pad, and the C-axis driving unit isinstalled between the B-axis driving unit and the drum pad to adjust ahorizontal position of the entirety of the arched drum pad.
 8. Thedetachment apparatus of claim 5, wherein movement values of the axes ofthe respective driving units are set for respective points from astarting point at which detachment of auxiliary substrates from theliquid crystal panel starts to an end point at which the detachmentends, and the axes of the respective driving units are moved verticallyor horizontally according to the set values.
 9. The detachment apparatusof claim 1, wherein the O-rings include a first O-ring having arectangular shape constituting a rim and a plurality of second O-ringsconnected to both sides of the first O-ring, the plurality of secondO-rings having a lattice shape.
 10. The detachment apparatus of claim 1,wherein the O-rings are made of natural rubber or silicon.
 11. Thedetachment apparatus of claim 9, further comprising vacuum compartmentsdemarcated by the first O-ring and the plurality of second O-rings, thevacuum compartments having an elongated rectangular shape, and includinga vacuum groove line having a trapezoid shape and a plurality ofabsorption holes formed in the vacuum groove line and extending to anupper surface of the arched drum pad for providing individual vacuum ineach of the vacuum compartments.
 12. The detachment apparatus of claim1, wherein a surface of the arched drum pad is coated with fluorine orcarbon nano-tubes to prevent damage to auxiliary substrates attached toboth sides of a process-completed liquid crystal panel in a cell statedue to static electricity.
 13. A method for fabricating a liquid crystaldisplay (LCD) device, the method comprising: providing a first auxiliarysubstrate and a second auxiliary substrate, and a first thin mothersubstrate and a second thin mother substrate; attaching the first andsecond auxiliary substrates to the first and second thin mothersubstrates, respectively; performing an array process on the firstmother substrate with the first auxiliary substrates attached thereto;performing a color filter process on the second mother substrate withthe second auxiliary substrate attached thereto; attaching the arrayprocess-finished first mother substrate and the color filterprocess-finished second mother substrate; providing a detachmentapparatus including an arched drum pad having O-rings formed on a lowersurface thereof and a plurality of vacuum compartments formed on thelower surface and demarcated by the O-rings; loading the attached firstand second mother substrates onto a table of the detachment apparatus;separating the second auxiliary substrate from the second mothersubstrate by using the arched drum pad; reversing the first and secondmother substrates without the second auxiliary substrate and loading thefirst and second mother substrates onto the table; and separating thefirst auxiliary substrate from the first mother substrate by using thearched drum pad.
 14. The method of claim 13, wherein the separating ofthe second auxiliary substrate from the second mother substratecomprises: lowering a front end of the arched drum pad andsimultaneously lifting a rear end thereof and absorbing a surface of thefront end of the second auxiliary substrate through the vacuumcompartments of the drum pad; and gradually lifting the front end of thearched drum pad with the second auxiliary substrate absorbed thereto,and simultaneously gradually lowering the rear end of the drum pad toseparate the second auxiliary substrate from the second mothersubstrate.
 15. The method of claim 14, wherein before the secondauxiliary substrate is separated, exposing push pin regions at bothcorners of the second auxiliary substrate and pushing the exposed pushpin regions with predetermined pressure by using bar-like push pins toform a gap knife entry space between the second auxiliary substrate andthe second mother substrate.
 16. The method of claim 15, wherein a gapknife is introduced into the gap knife entry space, the gap knife movedfrom one side to the other side of the table to detach edge portionsbetween the second auxiliary substrate and the second mother substrateto form an initial gap.
 17. The method of claim 13, wherein theseparating of the first auxiliary substrate from the first mothersubstrate comprises: lowering a front end of the arched drum pad andsimultaneously lifting a rear end thereof and absorbing a surface of thefront end of the first auxiliary substrate through the vacuumcompartments of the drum pad; and gradually lifting the front end of thearched drum pad with the first auxiliary substrate absorbed thereto, andsimultaneously gradually lowering the rear end of the drum pad toseparate the first auxiliary substrate from the first mother substrate.18. The method of claim 17, wherein before the first auxiliary substrateis separated, exposing push pin regions at both corners of the firstauxiliary substrate and are pushing the exposed push pin regions withpredetermined pressure by using bar-like push pins to form a gap knifeentry space between the first auxiliary substrate and the first mothersubstrate.
 19. The method of claim 18, wherein a gap knife is introducedinto the gap knife entry space, the gap knife moved from one side to theother side of the table to detach edge portions between the firstauxiliary substrate and the first mother substrate to form an initialgap.